1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
3 #include <linux/export.h>
4 #include <linux/reboot.h>
5 #include <linux/init.h>
9 #include <linux/sched.h>
10 #include <linux/tboot.h>
11 #include <linux/delay.h>
12 #include <linux/frame.h>
13 #include <acpi/reboot.h>
16 #include <asm/io_apic.h>
19 #include <asm/pgtable.h>
20 #include <asm/proto.h>
21 #include <asm/reboot_fixups.h>
22 #include <asm/reboot.h>
23 #include <asm/pci_x86.h>
24 #include <asm/virtext.h>
29 #include <linux/ctype.h>
30 #include <linux/mc146818rtc.h>
31 #include <asm/realmode.h>
32 #include <asm/x86_init.h>
36 * Power off function, if any
38 void (*pm_power_off
)(void);
39 EXPORT_SYMBOL(pm_power_off
);
42 * This is set if we need to go through the 'emergency' path.
43 * When machine_emergency_restart() is called, we may be on
44 * an inconsistent state and won't be able to do a clean cleanup
46 static int reboot_emergency
;
48 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
49 bool port_cf9_safe
= false;
52 * Reboot options and system auto-detection code provided by
53 * Dell Inc. so their systems "just work". :-)
57 * Some machines require the "reboot=a" commandline options
59 static int __init
set_acpi_reboot(const struct dmi_system_id
*d
)
61 if (reboot_type
!= BOOT_ACPI
) {
62 reboot_type
= BOOT_ACPI
;
63 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
70 * Some machines require the "reboot=b" or "reboot=k" commandline options,
71 * this quirk makes that automatic.
73 static int __init
set_bios_reboot(const struct dmi_system_id
*d
)
75 if (reboot_type
!= BOOT_BIOS
) {
76 reboot_type
= BOOT_BIOS
;
77 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
83 void __noreturn
machine_real_restart(unsigned int type
)
88 * Write zero to CMOS register number 0x0f, which the BIOS POST
89 * routine will recognize as telling it to do a proper reboot. (Well
90 * that's what this book in front of me says -- it may only apply to
91 * the Phoenix BIOS though, it's not clear). At the same time,
92 * disable NMIs by setting the top bit in the CMOS address register,
93 * as we're about to do peculiar things to the CPU. I'm not sure if
94 * `outb_p' is needed instead of just `outb'. Use it to be on the
95 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
98 CMOS_WRITE(0x00, 0x8f);
99 spin_unlock(&rtc_lock
);
102 * Switch back to the initial page table.
105 load_cr3(initial_page_table
);
107 write_cr3(real_mode_header
->trampoline_pgd
);
110 /* Jump to the identity-mapped low memory code */
112 asm volatile("jmpl *%0" : :
113 "rm" (real_mode_header
->machine_real_restart_asm
),
116 asm volatile("ljmpl *%0" : :
117 "m" (real_mode_header
->machine_real_restart_asm
),
122 #ifdef CONFIG_APM_MODULE
123 EXPORT_SYMBOL(machine_real_restart
);
125 STACK_FRAME_NON_STANDARD(machine_real_restart
);
128 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
130 static int __init
set_pci_reboot(const struct dmi_system_id
*d
)
132 if (reboot_type
!= BOOT_CF9_FORCE
) {
133 reboot_type
= BOOT_CF9_FORCE
;
134 pr_info("%s series board detected. Selecting %s-method for reboots.\n",
140 static int __init
set_kbd_reboot(const struct dmi_system_id
*d
)
142 if (reboot_type
!= BOOT_KBD
) {
143 reboot_type
= BOOT_KBD
;
144 pr_info("%s series board detected. Selecting %s-method for reboot.\n",
151 * This is a single dmi_table handling all reboot quirks.
153 static struct dmi_system_id __initdata reboot_dmi_table
[] = {
156 { /* Handle reboot issue on Acer Aspire one */
157 .callback
= set_kbd_reboot
,
158 .ident
= "Acer Aspire One A110",
160 DMI_MATCH(DMI_SYS_VENDOR
, "Acer"),
161 DMI_MATCH(DMI_PRODUCT_NAME
, "AOA110"),
166 { /* Handle problems with rebooting on Apple MacBook5 */
167 .callback
= set_pci_reboot
,
168 .ident
= "Apple MacBook5",
170 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
171 DMI_MATCH(DMI_PRODUCT_NAME
, "MacBook5"),
174 { /* Handle problems with rebooting on Apple MacBookPro5 */
175 .callback
= set_pci_reboot
,
176 .ident
= "Apple MacBookPro5",
178 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
179 DMI_MATCH(DMI_PRODUCT_NAME
, "MacBookPro5"),
182 { /* Handle problems with rebooting on Apple Macmini3,1 */
183 .callback
= set_pci_reboot
,
184 .ident
= "Apple Macmini3,1",
186 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
187 DMI_MATCH(DMI_PRODUCT_NAME
, "Macmini3,1"),
190 { /* Handle problems with rebooting on the iMac9,1. */
191 .callback
= set_pci_reboot
,
192 .ident
= "Apple iMac9,1",
194 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
195 DMI_MATCH(DMI_PRODUCT_NAME
, "iMac9,1"),
198 { /* Handle problems with rebooting on the iMac10,1. */
199 .callback
= set_pci_reboot
,
200 .ident
= "Apple iMac10,1",
202 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
203 DMI_MATCH(DMI_PRODUCT_NAME
, "iMac10,1"),
208 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */
209 .callback
= set_pci_reboot
,
210 .ident
= "ASRock Q1900DC-ITX",
212 DMI_MATCH(DMI_BOARD_VENDOR
, "ASRock"),
213 DMI_MATCH(DMI_BOARD_NAME
, "Q1900DC-ITX"),
218 { /* Handle problems with rebooting on ASUS P4S800 */
219 .callback
= set_bios_reboot
,
220 .ident
= "ASUS P4S800",
222 DMI_MATCH(DMI_BOARD_VENDOR
, "ASUSTeK Computer INC."),
223 DMI_MATCH(DMI_BOARD_NAME
, "P4S800"),
226 { /* Handle problems with rebooting on ASUS EeeBook X205TA */
227 .callback
= set_acpi_reboot
,
228 .ident
= "ASUS EeeBook X205TA",
230 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
231 DMI_MATCH(DMI_PRODUCT_NAME
, "X205TA"),
234 { /* Handle problems with rebooting on ASUS EeeBook X205TAW */
235 .callback
= set_acpi_reboot
,
236 .ident
= "ASUS EeeBook X205TAW",
238 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK COMPUTER INC."),
239 DMI_MATCH(DMI_PRODUCT_NAME
, "X205TAW"),
244 { /* Handle problems with rebooting on Certec BPC600 */
245 .callback
= set_pci_reboot
,
246 .ident
= "Certec BPC600",
248 DMI_MATCH(DMI_SYS_VENDOR
, "Certec"),
249 DMI_MATCH(DMI_PRODUCT_NAME
, "BPC600"),
254 { /* Handle problems with rebooting on Dell DXP061 */
255 .callback
= set_bios_reboot
,
256 .ident
= "Dell DXP061",
258 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
259 DMI_MATCH(DMI_PRODUCT_NAME
, "Dell DXP061"),
262 { /* Handle problems with rebooting on Dell E520's */
263 .callback
= set_bios_reboot
,
264 .ident
= "Dell E520",
266 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
267 DMI_MATCH(DMI_PRODUCT_NAME
, "Dell DM061"),
270 { /* Handle problems with rebooting on the Latitude E5410. */
271 .callback
= set_pci_reboot
,
272 .ident
= "Dell Latitude E5410",
274 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
275 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude E5410"),
278 { /* Handle problems with rebooting on the Latitude E5420. */
279 .callback
= set_pci_reboot
,
280 .ident
= "Dell Latitude E5420",
282 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
283 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude E5420"),
286 { /* Handle problems with rebooting on the Latitude E6320. */
287 .callback
= set_pci_reboot
,
288 .ident
= "Dell Latitude E6320",
290 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
291 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude E6320"),
294 { /* Handle problems with rebooting on the Latitude E6420. */
295 .callback
= set_pci_reboot
,
296 .ident
= "Dell Latitude E6420",
298 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
299 DMI_MATCH(DMI_PRODUCT_NAME
, "Latitude E6420"),
302 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
303 .callback
= set_bios_reboot
,
304 .ident
= "Dell OptiPlex 330",
306 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
307 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 330"),
308 DMI_MATCH(DMI_BOARD_NAME
, "0KP561"),
311 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
312 .callback
= set_bios_reboot
,
313 .ident
= "Dell OptiPlex 360",
315 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
316 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 360"),
317 DMI_MATCH(DMI_BOARD_NAME
, "0T656F"),
320 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
321 .callback
= set_bios_reboot
,
322 .ident
= "Dell OptiPlex 745",
324 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
325 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 745"),
328 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
329 .callback
= set_bios_reboot
,
330 .ident
= "Dell OptiPlex 745",
332 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
333 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 745"),
334 DMI_MATCH(DMI_BOARD_NAME
, "0MM599"),
337 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
338 .callback
= set_bios_reboot
,
339 .ident
= "Dell OptiPlex 745",
341 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
342 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 745"),
343 DMI_MATCH(DMI_BOARD_NAME
, "0KW626"),
346 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
347 .callback
= set_bios_reboot
,
348 .ident
= "Dell OptiPlex 760",
350 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
351 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 760"),
352 DMI_MATCH(DMI_BOARD_NAME
, "0G919G"),
355 { /* Handle problems with rebooting on the OptiPlex 990. */
356 .callback
= set_pci_reboot
,
357 .ident
= "Dell OptiPlex 990",
359 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
360 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 990"),
363 { /* Handle problems with rebooting on Dell 300's */
364 .callback
= set_bios_reboot
,
365 .ident
= "Dell PowerEdge 300",
367 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
368 DMI_MATCH(DMI_PRODUCT_NAME
, "PowerEdge 300/"),
371 { /* Handle problems with rebooting on Dell 1300's */
372 .callback
= set_bios_reboot
,
373 .ident
= "Dell PowerEdge 1300",
375 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
376 DMI_MATCH(DMI_PRODUCT_NAME
, "PowerEdge 1300/"),
379 { /* Handle problems with rebooting on Dell 2400's */
380 .callback
= set_bios_reboot
,
381 .ident
= "Dell PowerEdge 2400",
383 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
384 DMI_MATCH(DMI_PRODUCT_NAME
, "PowerEdge 2400"),
387 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */
388 .callback
= set_pci_reboot
,
389 .ident
= "Dell PowerEdge C6100",
391 DMI_MATCH(DMI_SYS_VENDOR
, "Dell"),
392 DMI_MATCH(DMI_PRODUCT_NAME
, "C6100"),
395 { /* Handle problems with rebooting on the Precision M6600. */
396 .callback
= set_pci_reboot
,
397 .ident
= "Dell Precision M6600",
399 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
400 DMI_MATCH(DMI_PRODUCT_NAME
, "Precision M6600"),
403 { /* Handle problems with rebooting on Dell T5400's */
404 .callback
= set_bios_reboot
,
405 .ident
= "Dell Precision T5400",
407 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
408 DMI_MATCH(DMI_PRODUCT_NAME
, "Precision WorkStation T5400"),
411 { /* Handle problems with rebooting on Dell T7400's */
412 .callback
= set_bios_reboot
,
413 .ident
= "Dell Precision T7400",
415 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
416 DMI_MATCH(DMI_PRODUCT_NAME
, "Precision WorkStation T7400"),
419 { /* Handle problems with rebooting on Dell XPS710 */
420 .callback
= set_bios_reboot
,
421 .ident
= "Dell XPS710",
423 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
424 DMI_MATCH(DMI_PRODUCT_NAME
, "Dell XPS710"),
427 { /* Handle problems with rebooting on Dell Optiplex 7450 AIO */
428 .callback
= set_acpi_reboot
,
429 .ident
= "Dell OptiPlex 7450 AIO",
431 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
432 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex 7450 AIO"),
436 /* Hewlett-Packard */
437 { /* Handle problems with rebooting on HP laptops */
438 .callback
= set_bios_reboot
,
439 .ident
= "HP Compaq Laptop",
441 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
442 DMI_MATCH(DMI_PRODUCT_NAME
, "HP Compaq"),
447 { /* Handle problems with rebooting on Sony VGN-Z540N */
448 .callback
= set_bios_reboot
,
449 .ident
= "Sony VGN-Z540N",
451 DMI_MATCH(DMI_SYS_VENDOR
, "Sony Corporation"),
452 DMI_MATCH(DMI_PRODUCT_NAME
, "VGN-Z540N"),
459 static int __init
reboot_init(void)
464 * Only do the DMI check if reboot_type hasn't been overridden
465 * on the command line
471 * The DMI quirks table takes precedence. If no quirks entry
472 * matches and the ACPI Hardware Reduced bit is set and EFI
473 * runtime services are enabled, force EFI reboot.
475 rv
= dmi_check_system(reboot_dmi_table
);
477 if (!rv
&& efi_reboot_required() && !efi_runtime_disabled())
478 reboot_type
= BOOT_EFI
;
482 core_initcall(reboot_init
);
484 static inline void kb_wait(void)
488 for (i
= 0; i
< 0x10000; i
++) {
489 if ((inb(0x64) & 0x02) == 0)
495 static void vmxoff_nmi(int cpu
, struct pt_regs
*regs
)
497 cpu_emergency_vmxoff();
500 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */
501 static void emergency_vmx_disable_all(void)
503 /* Just make sure we won't change CPUs while doing this */
507 * We need to disable VMX on all CPUs before rebooting, otherwise
508 * we risk hanging up the machine, because the CPU ignore INIT
509 * signals when VMX is enabled.
511 * We can't take any locks and we may be on an inconsistent
512 * state, so we use NMIs as IPIs to tell the other CPUs to disable
515 * For safety, we will avoid running the nmi_shootdown_cpus()
516 * stuff unnecessarily, but we don't have a way to check
517 * if other CPUs have VMX enabled. So we will call it only if the
518 * CPU we are running on has VMX enabled.
520 * We will miss cases where VMX is not enabled on all CPUs. This
521 * shouldn't do much harm because KVM always enable VMX on all
522 * CPUs anyway. But we can miss it on the small window where KVM
523 * is still enabling VMX.
525 if (cpu_has_vmx() && cpu_vmx_enabled()) {
526 /* Disable VMX on this CPU. */
529 /* Halt and disable VMX on the other CPUs */
530 nmi_shootdown_cpus(vmxoff_nmi
);
536 void __attribute__((weak
)) mach_reboot_fixups(void)
541 * To the best of our knowledge Windows compatible x86 hardware expects
542 * the following on reboot:
544 * 1) If the FADT has the ACPI reboot register flag set, try it
545 * 2) If still alive, write to the keyboard controller
546 * 3) If still alive, write to the ACPI reboot register again
547 * 4) If still alive, write to the keyboard controller again
548 * 5) If still alive, call the EFI runtime service to reboot
549 * 6) If no EFI runtime service, call the BIOS to do a reboot
551 * We default to following the same pattern. We also have
552 * two other reboot methods: 'triple fault' and 'PCI', which
553 * can be triggered via the reboot= kernel boot option or
556 * This means that this function can never return, it can misbehave
557 * by not rebooting properly and hanging.
559 static void native_machine_emergency_restart(void)
563 int orig_reboot_type
= reboot_type
;
566 if (reboot_emergency
)
567 emergency_vmx_disable_all();
569 tboot_shutdown(TB_SHUTDOWN_REBOOT
);
571 /* Tell the BIOS if we want cold or warm reboot */
572 mode
= reboot_mode
== REBOOT_WARM
? 0x1234 : 0;
573 *((unsigned short *)__va(0x472)) = mode
;
576 * If an EFI capsule has been registered with the firmware then
577 * override the reboot= parameter.
579 if (efi_capsule_pending(NULL
)) {
580 pr_info("EFI capsule is pending, forcing EFI reboot.\n");
581 reboot_type
= BOOT_EFI
;
585 /* Could also try the reset bit in the Hammer NB */
586 switch (reboot_type
) {
589 reboot_type
= BOOT_KBD
;
593 mach_reboot_fixups(); /* For board specific fixups */
595 for (i
= 0; i
< 10; i
++) {
598 outb(0xfe, 0x64); /* Pulse reset low */
601 if (attempt
== 0 && orig_reboot_type
== BOOT_ACPI
) {
603 reboot_type
= BOOT_ACPI
;
605 reboot_type
= BOOT_EFI
;
610 efi_reboot(reboot_mode
, NULL
);
611 reboot_type
= BOOT_BIOS
;
615 machine_real_restart(MRR_BIOS
);
617 /* We're probably dead after this, but... */
618 reboot_type
= BOOT_CF9_SAFE
;
622 port_cf9_safe
= true;
627 u8 reboot_code
= reboot_mode
== REBOOT_WARM
? 0x06 : 0x0E;
628 u8 cf9
= inb(0xcf9) & ~reboot_code
;
629 outb(cf9
|2, 0xcf9); /* Request hard reset */
631 /* Actually do the reset */
632 outb(cf9
|reboot_code
, 0xcf9);
635 reboot_type
= BOOT_TRIPLE
;
639 idt_invalidate(NULL
);
640 __asm__
__volatile__("int3");
642 /* We're probably dead after this, but... */
643 reboot_type
= BOOT_KBD
;
649 void native_machine_shutdown(void)
651 /* Stop the cpus and apics */
652 #ifdef CONFIG_X86_IO_APIC
654 * Disabling IO APIC before local APIC is a workaround for
655 * erratum AVR31 in "Intel Atom Processor C2000 Product Family
656 * Specification Update". In this situation, interrupts that target
657 * a Logical Processor whose Local APIC is either in the process of
658 * being hardware disabled or software disabled are neither delivered
659 * nor discarded. When this erratum occurs, the processor may hang.
661 * Even without the erratum, it still makes sense to quiet IO APIC
662 * before disabling Local APIC.
669 * Stop all of the others. Also disable the local irq to
670 * not receive the per-cpu timer interrupt which may trigger
671 * scheduler's load balance.
679 #ifdef CONFIG_HPET_TIMER
684 x86_platform
.iommu_shutdown();
688 static void __machine_emergency_restart(int emergency
)
690 reboot_emergency
= emergency
;
691 machine_ops
.emergency_restart();
694 static void native_machine_restart(char *__unused
)
696 pr_notice("machine restart\n");
700 __machine_emergency_restart(0);
703 static void native_machine_halt(void)
705 /* Stop other cpus and apics */
708 tboot_shutdown(TB_SHUTDOWN_HALT
);
713 static void native_machine_power_off(void)
720 /* A fallback in case there is no PM info available */
721 tboot_shutdown(TB_SHUTDOWN_HALT
);
724 struct machine_ops machine_ops __ro_after_init
= {
725 .power_off
= native_machine_power_off
,
726 .shutdown
= native_machine_shutdown
,
727 .emergency_restart
= native_machine_emergency_restart
,
728 .restart
= native_machine_restart
,
729 .halt
= native_machine_halt
,
730 #ifdef CONFIG_KEXEC_CORE
731 .crash_shutdown
= native_machine_crash_shutdown
,
735 void machine_power_off(void)
737 machine_ops
.power_off();
740 void machine_shutdown(void)
742 machine_ops
.shutdown();
745 void machine_emergency_restart(void)
747 __machine_emergency_restart(1);
750 void machine_restart(char *cmd
)
752 machine_ops
.restart(cmd
);
755 void machine_halt(void)
760 #ifdef CONFIG_KEXEC_CORE
761 void machine_crash_shutdown(struct pt_regs
*regs
)
763 machine_ops
.crash_shutdown(regs
);
768 /* This is the CPU performing the emergency shutdown work. */
769 int crashing_cpu
= -1;
771 #if defined(CONFIG_SMP)
773 static nmi_shootdown_cb shootdown_callback
;
775 static atomic_t waiting_for_crash_ipi
;
776 static int crash_ipi_issued
;
778 static int crash_nmi_callback(unsigned int val
, struct pt_regs
*regs
)
782 cpu
= raw_smp_processor_id();
785 * Don't do anything if this handler is invoked on crashing cpu.
786 * Otherwise, system will completely hang. Crashing cpu can get
787 * an NMI if system was initially booted with nmi_watchdog parameter.
789 if (cpu
== crashing_cpu
)
793 shootdown_callback(cpu
, regs
);
795 atomic_dec(&waiting_for_crash_ipi
);
796 /* Assume hlt works */
804 static void smp_send_nmi_allbutself(void)
806 apic
->send_IPI_allbutself(NMI_VECTOR
);
810 * Halt all other CPUs, calling the specified function on each of them
812 * This function can be used to halt all other CPUs on crash
813 * or emergency reboot time. The function passed as parameter
814 * will be called inside a NMI handler on all CPUs.
816 void nmi_shootdown_cpus(nmi_shootdown_cb callback
)
821 /* Make a note of crashing cpu. Will be used in NMI callback. */
822 crashing_cpu
= safe_smp_processor_id();
824 shootdown_callback
= callback
;
826 atomic_set(&waiting_for_crash_ipi
, num_online_cpus() - 1);
827 /* Would it be better to replace the trap vector here? */
828 if (register_nmi_handler(NMI_LOCAL
, crash_nmi_callback
,
829 NMI_FLAG_FIRST
, "crash"))
830 return; /* Return what? */
832 * Ensure the new callback function is set before sending
837 smp_send_nmi_allbutself();
839 /* Kick CPUs looping in NMI context. */
840 WRITE_ONCE(crash_ipi_issued
, 1);
842 msecs
= 1000; /* Wait at most a second for the other cpus to stop */
843 while ((atomic_read(&waiting_for_crash_ipi
) > 0) && msecs
) {
848 /* Leave the nmi callback set */
852 * Check if the crash dumping IPI got issued and if so, call its callback
853 * directly. This function is used when we have already been in NMI handler.
856 void run_crash_ipi_callback(struct pt_regs
*regs
)
858 if (crash_ipi_issued
)
859 crash_nmi_callback(0, regs
);
862 /* Override the weak function in kernel/panic.c */
863 void nmi_panic_self_stop(struct pt_regs
*regs
)
866 /* If no CPU is preparing crash dump, we simply loop here. */
867 run_crash_ipi_callback(regs
);
872 #else /* !CONFIG_SMP */
873 void nmi_shootdown_cpus(nmi_shootdown_cb callback
)
875 /* No other CPUs to shoot down */
878 void run_crash_ipi_callback(struct pt_regs
*regs
)